Self powered locks have been known for some time. The self powered locks have been of two general types. A first type has been where the power is provided by movement of a member such as a knob or handle which causes generation of power and the entry of the combination by either a key or card carrying a code. The generation of power is separate from the code entry device.
The other type of such self powered lock is exemplified by the lock disclosed in U.S. Pat. No. 5,061,923 issued to Miller et al. In this type lock the same mechanism is used for generation of power for the lock and for the creation of the electronic pulses.
The Miller et al. lock has a permanently engaged drive from a dial to a stepper motor which outputs voltage pulses in both directions of rotations and provides the same pulses to the microprocessor for purposes of entering the combination into the lock or controlling the functions of the lock.